Draining Radiator Only for Maintenance?

[SR77]

Hey guys. What is your opinion on draining the radiator and recovery bottle only for coolant maintenance instead of a complete system flush? The antifreeze in my car states its good for 5+ years, and I am thinking of just draining the rad. and recovery bottle every 1.5-2 years as maintenance instead of a flush every 5+. I am thinking by adding fresh coolant in that should give me the same coolant performance as letting the coolant go its full life and get dirty and then having to flush the system. Anyone else maintain their coolant system this way?
Plus, I also hate doing complete flushes as it takes forever and I feel that i don't always get all the old stuff completely out or also run the chance of not getting the right mixture back in.

 

[bigmike]

I've pretty much always done that routine with all my vehicles. I'd rather do it that way because it's easier. Just make sure you use compatible coolant in the proper mixture.

 

[demarpaint]

I've done it since a mechanic buddy of mine suggested it to me back in the 1970's. The oldest of my fleet, my 88 E-150 has seen this method every 2 years since I bought it in 1988. The cooling system is pristine! It is easier, faster, and IMO works as well or better than a complete flush. The key to being successful is not to let the coolant go to the max limit of its life stated on the label. Opinions will certainly vary, but it has worked for me for many many years.

I empty the radiator cold with the engine off, and run the garden hose through it for a few minutes, and let it drain. I'll pour a gallon or so of distilled water through it to get the garden hose water out. I get the proper mix of AF and distilled water fill it and burp the system. Then I check the mix with the Prestone tool I have, after the van has been driven a while and has cooled down.

I use full strength AF and mix it myself with distilled water, and make sure it is the proper AF for the vehicle.

 

[JHZR2]

Thats how I do it without issue.

 

[MrBeachcomber]

Originally Posted By: SR77
...What is your opinion on draining the radiator and recovery bottle only for coolant maintenance instead of a complete system flush?

Inspecting the coolant recovery bottle and internal radiator condition on a regular basis and testing the coolant with coolant test strips is more effective than just draining both of them, inspecting, and replacing the old coolant with new.

If you're sludging up either the radiator or the coolant recovery bottle, you'll need to flush the coolant system including the engine block and heater core. If the coolant tests weak, you'll need to replace it regardless of how long it's been used.

You'll save time and money doing the inspection/testing method; however YMMV. Use the method that gives you piece of mind.

 

[mechanicx]

There's nothing wrong with just draining the radiator. But you should do it frequently. You want to shoot for about 4 drains over the service life of the coolant so most all of the old coolant will be changed by the end. So about once every 1-2 years. It's not really much different in concept of 4x transmission drains or power steering siphon refills over fluid service life vs. flushing. It is really just as effective.

 

[pbm]

I used to flush my radiator every year or two when cars had traditional coolants. I started doing the D&R method that you suggest with my current vehicles because it is harder to find extended life coolants in 'full strength' versions. It is easier to drain and refill with the precise 50/50 mix from the jug.

With my 2001 Accord I used PEAK Global A/F doing a D&R approx. every 20K. When I had my T-belt changed at 93K the water pump looked brand new. If I had known then what I know now, I probably would have went longer than 20K between D&R's (the E-L coolants work as advertised in an engine with proper gasketing, etc...)

 

[eljefino]

Great idea. Of course if you see rust you'll want a flush.

My neglected cherokee I bought from my work had muddy brown soup for coolant. Its twin, bought the same time, overheated with only an idiot light to warn the driver.

The all iron block and head had lots to shed. YMMV. Also that stupid cherokee's radiator petcock was halfway up the side, so I did a lower hose pull.

 

[demarpaint]

The key here is not to let the coolant get into that muddy condition. For people like myself who are the original owners of the vehicle the drain and refill the radiator method works good. For people who bought a car used with unknown history a flush and refill would be best. Then once everything is good, a drain and refill of the radiator every 24 months would be OK to maintain the system. JMO

 

[Petersubaru]

within the family stable of cars, two are almost 25 yrs old with aluminum rads that are original when the cars were new..each car has more miles on it then most...drain and fill every yr to 1.5 yrs..even the hoses are original..same goes for the auto tranny and PSteering

 

[KrisZ]

My Mazda's manual actually has a procedure for radiator drain and fill, and that's what they call "coolant change", they recommend this "change" every 2 years with green coolant.

 

[MC5W20]

Originally Posted By: SR77
Hey guys. What is your opinion on draining the radiator and recovery bottle only for coolant maintenance instead of a complete system flush? The antifreeze in my car states its good for 5+ years, and I am thinking of just draining the rad. and recovery bottle every 1.5-2 years as maintenance instead of a flush every 5+. I am thinking by adding fresh coolant in that should give me the same coolant performance as letting the coolant go its full life and get dirty and then having to flush the system. Anyone else maintain their coolant system this way?
Plus, I also hate doing complete flushes as it takes forever and I feel that i don't always get all the old stuff completely out or also run the chance of not getting the right mixture back in.


I always used to do flush and refill's. They were time consuming and it was I thought you were supposed to do. I have also had two vehciles develop leaks on me after doing a flush. After being a member here I read of other members doing the method you describe, and how it had worked for them for many years with no problems.

I was sold. However, I do mine once a year, and did the first one at 4 years. It only cost $13 for a gallon of coolant, and it only takes 30 min. to do a drain and refill. The fresh coolant keeps the coolant fresh, and the yearly drain gets some sediment out and doesn't allow it to build up to a harmful level.

 

[M1Accord]

I think if you still the same coolant all the time then you don't need to flush. The coolant mileage probably states 100-150k miles so I think you're perfectly fine with just drain and refill every 5 years if you drive 2/3 or less than the maximum mileage distance. If you do drive a lot, then I would stick with 3-4 years because many products are conservative with their life span. For example, dino juice can easily go 7500 miles but most people and place still recommend 3k/3mo.

 

[SR77]

Thanks for all the replies. Looks like I am gonna stick to the plan then!

I was gonna ask this in a new thread but since it was brought up I will just post it here. Is there a "best" way to burp the system? Best way meaning quick and easy. The last Radiator drop I did, only a 1/4 of what came out went back in. Had to run the engine, then let it cool back down and let the vacumm created pull the coolant in so I could keep adding more. This takes a good amount of time waiting for the cool down periods each time. Is there a better way that you guys use when refilling your radiator with coolant?

 

[demarpaint]

Originally Posted By: SR77
Thanks for all the replies. Looks like I am gonna stick to the plan then!

I was gonna ask this in a new thread but since it was brought up I will just post it here. Is there a "best" way to burp the system? Best way meaning quick and easy. The last Radiator drop I did, only a 1/4 of what came out went back in. Had to run the engine, then let it cool back down and let the vacumm created pull the coolant in so I could keep adding more. This takes a good amount of time waiting for the cool down periods each time. Is there a better way that you guys use when refilling your radiator with coolant?


Here's how I did it, and what others had to say. HTH

https://bobistheoilguy.com/forums/posts/2032833/


Jacking the front of the vehicle making the radiator the highest point of the engine is a big help if you don't have a bleeder.